The hotel room number in the 1952 film Don't Bother to Knock, starring Richard Widmark and Marilyn Monroe. Marilyn's character (Nell Forbes) is a lonely blonde who has recently been released from a mental institution. [McCranie]

The smallest prime whose fourth power is zeroless pandigital (i.e., containing all digits from 1 to 9). [Gupta]

The largest prime less than 10000 such that 2p-F(p) is also prime, where F(p) is the pth Fibonacci number. [Opao]

809 is the start of 21 consecutive primes which alternate between the forms 6n - 1 and 6n + 1. The smallest start of 22 such primes is the much larger 3954889. [Andersen]

Largest known prime p such that T(p) is prime in Juricevic
conjecture on classification of Lehmer triples. Juricevic
conjectured an infinite number of such primes. Yu Tsumura
proved that T(p) is infinitely often composite. [Post]

(There are 3 curios for this number that have not yet been approved by an editor.)